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Item Binding Of Flexible And Constrained Ligands To The Grb2 Sh2 Domain: Structural Effects Of Ligand Preorganization(2010-10) Clements, John H.; DeLorbe, John E.; Benfield, Aaron P.; Martin, Stephen F.; Clements, John H.; DeLorbe, John E.; Benfield, Aaron P.; Martin, Stephen F.Structures of the Grb2 SH2 domain complexed with a series of pseudopeptides containing flexible (benzyl succinate) and constrained (aryl cyclopropanedicarboxylate) replacements of the phosphotyrosine (pY) residue in tripeptides derived from Ac-pYXN-NH(2) (where X = V, I, E and Q) were elucidated by X-ray crystallography. Complexes of flexible/constrained pairs having the same pY + 1 amino acid were analyzed in order to ascertain what structural differences might be attributed to constraining the phosphotyrosine replacement. In this context, a given structural dissimilarity between complexes was considered to be significant if it was greater than the corresponding difference in complexes coexisting within the same asymmetric unit. The backbone atoms of the domain generally adopt a similar conformation and orientation relative to the ligands in the complexes of each flexible/constrained pair, although there are some significant differences in the relative orientations of several loop regions, most notably in the BC loop that forms part of the binding pocket for the phosphate group in the tyrosine replacements. These variations are greater in the set of complexes of constrained ligands than in the set of complexes of flexible ligands. The constrained ligands make more direct polar contacts to the domain than their flexible counterparts, whereas the more flexible ligand of each pair makes more single-water-mediated contacts to the domain; there was no correlation between the total number of protein-ligand contacts and whether the phosphotyrosine replacement of the ligand was preorganized. The observed differences in hydrophobic interactions between the complexes of each flexible/constrained ligand pair were generally similar to those observed upon comparing such contacts in coexisting complexes. The average adjusted B factors of the backbone atoms of the domain and loop regions are significantly greater in the complexes of constrained ligands than in the complexes of the corresponding flexible ligands, suggesting greater thermal motion in the crystalline state in the former complexes. There was no apparent correlation between variations in crystal packing and observed structural differences or similarities in the complexes of flexible and constrained ligands, but the possibility that crystal packing might result in structural variations cannot be rigorously excluded. Overall, it appears that there are more variations in the three-dimensional structure of the protein and the ligand in complexes of the constrained ligands than in those of their more flexible counterparts.Item The Cosmic Near Infrared Background. III. Fluctuations, Reionization, And The Effects Of Minimum Mass And Self-Regulation(2012-05) Fernandez, Elizabeth R.; Iliev, Illian T.; Komatsu, Eiichiro; Shapiro, Paul R.; Komatsu, Eiichiro; Shapiro, Paul R.Current observations suggest that the universe was reionized sometime before z similar to 6. One way to observe this epoch of the universe is through the Near Infrared Background (NIRB), which contains information about galaxies which may be too faint to be observed individually. We calculate the angular power spectrum (C-l) of the NIRB fluctuations caused by the distribution of these galaxies. Assuming a complete subtraction of any post-reionization component, C-l will be dominated by galaxies responsible for completing reionization (e.g., z similar to 6). The shape of C-l at high l is sensitive to the amount of nonlinear bias of dark matter halos hosting galaxies. As the nonlinear bias depends on the mass of these halos, we can use the shape of C-l to infer typical masses of dark matter halos responsible for completing reionization. We extend our previous study by using a higher-resolution N-body simulation, which can resolve halos down to 10(8) M-circle dot. We also include improved radiative transfer, which allows for the suppression of star formation in small-mass halos due to photoionization heating. As the nonlinear bias enhances the dark matter halo power spectrum on small scales, we find that C-l is steeper for the case with a complete suppression of small sources or partial suppression of star formation in small halos (the minimum galaxy mass is M-min = 10(9)M(circle dot) in ionized regions and M-min = 10(8)M(circle dot) in neutral regions) than for the case in which these small halos were unsuppressed. In all cases, we do not see a turnover toward high l in the shape of l(2)C(l).Item The Effect Of Turbulent Intermittency On The Deflagration To Detonation Transition In Supernova Ia Explosions(2008-07) Pan, Lubin; Wheeler, J. Craig; Scalo, John; Pan, Lubin; Wheeler, J. Craig; Scalo, JohnWe examine the effects of turbulent intermittency on the deflagration to detonation transition (DDT) in Type Ia supernovae. The Zel'dovich mechanism for DDT requires the formation of a nearly isothermal region of mixed ash and fuel that is larger than a critical size. We primarily consider the hypothesis by Khokhlov et al. and Niemeyer and Woosley that the nearly isothermal, mixed region is produced when the flame makes the transition to the distributed regime. We use two models for the distribution of the turbulent velocity fluctuations to estimate the probability as a function of the density in the exploding white dwarf that a given region of critical size is in the distributed regime due to strong local turbulent stretching of the flame structure. We also estimate lower limits on the number of such regions as a function of density. We find that the distributed regime, and hence perhaps DDT, occurs in a local region of critical size at a density at least a factor of 2-3 larger than predicted for mean conditions that neglect intermittency. This factor makes the transition density much larger than the empirical value from observations in most situations. We also consider the intermittency effect on the more stringent conditions for DDT by Lisewski et al. and Woosley. We find that a turbulent velocity of 10(8) cm s(-1) in a region of size 10(6) cm, as required by Lisewski et al., is rare. We expect that intermittency has a weaker effect on the Woosley model with a stronger DDT criterion. The predicted transition density from this criterion remains below 10(7) g cm(-3) after accounting for intermittency using our intermittency models.Item First Search For Gravitational Waves From The Youngest Known Neutron Star(2010-10) Abadie, J.; Abbott, B. P.; Abbott, R.; Abernathy, M.; Adams, C.; Adhikari, R.; Ajith, P.; Allen, B.; Allen, G.; Ceron, E. A.; Amin, R. S.; Anderson, S. B.; Anderson, W. G.; Arain, M. A.; Araya, M.; Aronsson, M.; Aso, Y.; Aston, S.; Atkinson, D. E.; Aufmuth, P.; Aulbert, C.; Babak, S.; Baker, P.; Ballmer, S.; Barker, D.; Barnum, S.; Barr, B.; Barriga, P.; Barsotti, L.; Barton, M. A.; Bartos, I.; Bassiri, R.; Bastarrika, M.; Bauchrowitz, J.; Behnke, B.; Benacquista, M.; Bertolini, A.; Betzwieser, J.; Beveridge, N.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biswas, R.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bland, B.; Bock, O.; Bodiya, T. P.; Bondarescu, R.; Bork, R.; Born, M.; Bose, S.; Boyle, M.; Brady, P. R.; Braginsky, V. B.; Brau, J. E.; Breyer, J.; Bridges, D. O.; Brinkmann, M.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Buonanno, A.; Burguet-Castell, J.; Burmeister, O.; Byer, R. L.; Cadonati, L.; Camp, J. B.; Campsie, P.; Cannizzo, J.; Cannon, K. C.; Cao, J.; Capano, C.; Caride, S.; Caudill, S.; Cavaglia, M.; Cepeda, C.; Chalermsongsak, T.; Chalkley, E.; Charlton, P.; Chelkowski, S.; Chen, Y.; Christensen, N.; Chua, S. S. Y.; Chung, C. T. Y.; Clark, D.; Clark, J.; Clayton, J. H.; Conte, R.; Cook, D.; Corbitt, T. R.; Cornish, N.; Costa, C. A.; Coward, D.; Coyne, D. C.; Creighton, J. D. E.; Creighton, T. D.; Cruise, A. M.; Culter, R. M.; Cumming, A.; Cunningham, L.; Dahl, K.; Danilishin, S. L.; Dannenberg, R.; Danzmann, K.; Das, K.; Daudert, B.; Davies, G.; Davis, A.; Daw, E. J.; Dayanga, T.; DeBra, D.; Degallaix, J.; Dergachev, V.; DeRosa, R.; DeSalvo, R.; Devanka, P.; Dhurandhar, S.; Di Palma, I.; Diaz, M.; Donovan, F.; Dooley, K. L.; Doomes, E. E.; Dorsher, S.; Douglas, E. S. D.; Drever, R. W. P.; Driggers, J. C.; Dueck, J.; Dumas, J. C.; Eberle, T.; Edgar, M.; Edwards, M.; Effler, A.; Ehrens, P.; Engel, R.; Etzel, T.; Evans, M.; Evans, T.; Fairhurst, S.; Fan, Y.; Farr, B. F.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Finn, L. S.; Flanigan, M.; Flasch, K.; Foley, S.; Forrest, C.; Forsi, E.; Fotopoulos, N.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Friedrich, D.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Garofoli, J. A.; Gholami, I.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Gill, C.; Goetz, E.; Goggin, L. M.; Gonzalez, G.; Gorodetsky, M. L.; Goler, S.; Graef, C.; Grant, A.; Gras, S.; Gray, C.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Grosso, R.; Grote, H.; Grunewald, S.; Gustafson, E. K.; Gustafson, R.; Hage, B.; Hall, P.; Hallam, J. M.; Hammer, Derek; Hammond, G.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Haughian, K.; Hayama, K.; Heefner, J.; Heng, I. S.; Heptonstall, A.; Hewitson, M.; Hild, S.; Hirose, E.; Hoak, D.; Hodge, K. A.; Holt, K.; Hosken, D. J.; Hough, J.; Howell, E.; Hoyland, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.; Ju, L.; Kalmus, P.; Kalogera, V.; Kandhasamy, S.; Kanner, J.; Katsavounidis, E.; Kawabe, K.; Kawamura, S.; Kawazoe, F.; Kells, W.; Keppel, D. G.; Khalaidovski, A.; Khalili, F. Y.; Khazanov, E. A.; Kim, H.; King, P. J.; Kinzel, D. L.; Kissel, J. S.; Klimenko, S.; Kondrashov, V.; Kopparapu, R.; Koranda, S.; Kozak, D.; Krause, T.; Kringel, V.; Krishnamurthy, S.; Krishnan, B.; Kuehn, G.; Kullman, J.; Kumar, R.; Kwee, P.; Landry, M.; Lang, M.; Lantz, B.; Lastzka, N.; Lazzarini, A.; Leaci, P.; Leong, J.; Leonor, I.; Li, J.; Lin, H.; Lindquist, P. E.; Lockerbie, N. A.; Lodhia, D.; Lormand, M.; Lu, P.; Luan, J.; Lubinski, M.; Lucianetti, A.; Luck, H.; Lundgren, A.; Machenschalk, B.; MacInnis, M.; Mageswaran, M.; Mailand, K.; Mak, C.; Mandel, I.; Mandic, V.; Marka, S.; Marka, Z.; Maros, E.; Martin, I. W.; Martin, R. M.; Marx, J. N.; Mason, K.; Matichard, F.; Matone, L.; Matzner, R. A.; Mavalvala, N.; McCarthy, R.; McClelland, D. E.; McGuire, S. C.; McIntyre, G.; McIvor, G.; McKechan, D. J. A.; Meadors, G.; Mehmet, M.; Meier, T.; Melatos, A.; Melissinos, A. C.; Mendell, G.; Menendez, D. F.; Mercer, R. A.; Merill, L.; Meshkov, S.; Messenger, C.; Meyer, M. S.; Miao, H.; Miller, J.; Mino, Y.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moe, B.; Mohanty, S. D.; Mohapatra, S. R. P.; Moraru, D.; Moreno, G.; Morioka, T.; Mors, K.; Mossavi, K.; MowLowry, C.; Mueller, G.; Mukherjee, S.; Mullavey, A.; Muller-Ebhardt, H.; Munch, J.; Murray, P. G.; Nash, T.; Nawrodt, R.; Nelson, J.; Newton, G.; Nishizawa, A.; Nolting, D.; Ochsner, E.; O'Dell, J.; Ogin, G. H.; Oldenburg, R. G.; O'Reilly, B.; O'Shaughnessy, R.; Osthelder, C.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Page, A.; Pan, Y.; Pankow, C.; Papa, M. A.; Pareja, M.; Patel, P.; Pedraza, M.; Pekowsky, L.; Penn, S.; Peralta, C.; Perreca, A.; Pickenpack, M.; Pinto, I. M.; Pitkin, M.; Pletsch, H. J.; Plissi, M. V.; Postiglione, F.; Predoi, V.; Price, L. R.; Prijatelj, M.; Principe, M.; Prix, R.; Prokhorov, L.; Puncken, O.; Quetschke, V.; Raab, F. J.; Radke, T.; Radkins, H.; Raffai, P.; Rakhmanov, M.; Rankins, B.; Raymond, V.; Reed, C. M.; Reid, T. R. S.; Reitze, D. H.; Riesen, R.; Riles, K.; Roberts, P.; Robertson, N. A.; Robinson, C.; Robinson, Edward L.; Roddy, S.; Rover, C.; Rollins, J.; Romano, J. D.; Romie, J. H.; Rowan, S.; Rudiger, A.; Ryan, K.; Sakata, S.; Sakosky, M.; Salemi, F.; Sammut, L.; de la Jordana, L. S.; Sandberg, V.; Sannibale, V.; Santamaria, L.; Santostasi, G.; Saraf, S.; Sathyaprakash, B. S.; Sato, S.; Satterthwaite, M.; Saulson, P. R.; Savage, R.; Schilling, R.; Schnabel, R.; Schofield, R.; Schulz, B.; Schutz, B. F.; Schwinberg, P.; Scott, J.; Scott, S. M.; Searle, A. C.; Seifert, F.; Sellers, D.; Sengupta, A. S.; Sergeev, A.; Shaddock, D.; Shapiro, B.; Shawhan, P.; Shoemaker, D. H.; Sibley, A.; Siemens, X.; Sigg, D.; Singer, A.; Sintes, A. M.; Skelton, G.; Slagmolen, B. J. J.; Slutsky, J.; Smith, J. R.; Smith, Mathew R.; Smith, N. D.; Somiya, K.; Sorazu, B.; Speirits, F. C.; Stein, A. J.; Stein, L. C.; Steinlechner, S.; Steplewski, S.; Stochino, A.; Stone, R.; Strain, K. A.; Strigin, S.; Stroeer, A.; Stuver, A. L.; Summerscales, T. Z.; Sung, M.; Susmithan, S.; Sutton, P. J.; Talukder, D.; Tanner, D. B.; Tarabrin, S. P.; Taylor, J. R.; Taylor, R.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Thuring, A.; Titsler, C.; Tokmakov, K. V.; Torres, C.; Torrie, C. I.; Traylor, G.; Trias, M.; Tseng, K.; Ugolini, D.; Urbanek, K.; Vahlbruch, H.; Vaishnav, B.; Vallisneri, M.; Van Den Broeck, C.; van der Sluys, M. V.; van Veggel, A. A.; Vass, S.; Vaulin, R.; Vecchio, A.; Veitch, J.; Veitch, P. J.; Veltkamp, C.; Villar, Ashley; Vorvick, C.; Vyachanin, S. P.; Waldman, S. J.; Wallace, L.; Wanner, A.; Ward, R. L.; Wei, P.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.; Wen, S.; Wessels, P.; West, M.; Westphal, T.; Wette, K.; Whelan, J. T.; Whitcomb, S. E.; White, D. J.; Whiting, B. F.; Wilkinson, C.; Willems, P. A.; Williams, L.; Willke, B.; Winkelmann, L.; Winkler, W.; Wipf, C. C.; Wiseman, A. G.; Woan, G.; Wooley, R.; Worden, J.; Yakushin, I.; Yamamoto, H.; Yamamoto, K.; Yeaton-Massey, D.; Yoshida, S.; Yu, P. P.; Zanolin, M.; Zhang, L.; Zhang, Z.; Zhao, C.; Zotov, N.; Zucker, M. E.; Zweizig, J.; Ligo Sci Collaboration; Frei, M.; Krause, T.; Matzner, R.A.; McIvor, G.We present a search for periodic gravitational waves from the neutron star in the supernova remnant Cassiopeia A. The search coherently analyzes data in a 12 day interval taken from the fifth science run of the Laser Interferometer Gravitational-Wave Observatory. It searches gravitational-wave frequencies from 100 to 300 Hz and covers a wide range of first and second frequency derivatives appropriate for the age of the remnant and for different spin-down mechanisms. No gravitational-wave signal was detected. Within the range of search frequencies, we set 95% confidence upper limits of (0.7-1.2) x 10(-24) on the intrinsic gravitational-wave strain, (0.4-4) x 10(-4) on the equatorial ellipticity of the neutron star, and 0.005-0.14 on the amplitude of r-mode oscillations of the neutron star. These direct upper limits beat indirect limits derived from energy conservation and enter the range of theoretical predictions involving crystalline exotic matter or runaway r-modes. This paper is also the first gravitational-wave search to present upper limits on the r-mode amplitude.Item Five Kepler Target Stars That Show Multiple Transiting Exoplanet Candidates(2010-12) Steffen, Jason H.; Batalha, Natalie M.; Borucki, William J.; Buchhave, Lars A.; Caldwell, Douglas A.; Cochran, William D.; Endl, Michael; Fabrycky, Daniel C.; Fressin, Francois; Ford, Eric B.; Fortney, Jonathan J.; Haas, Michael J.; Holman, Matthew J.; Howell, Steve B.; Isaacson, Howard; Jenkins, Jon M.; Koch, David; Latham, David W.; Lissauer, Jack J.; Moorhead, Althea V.; Morehead, Robert C.; Marcy, Geoffrey; MacQueen, Phillip J.; Quinn, Samuel N.; Ragozzine, Darin; Rowe, Jason F.; Sasselov, Dimitar D.; Seager, Sara; Torres, Guillermo; Welsh, William F.; Cochran, William D.; Endl, Michael; MacQueen, Phillip J.We present and discuss five candidate exoplanetary systems identified with the Kepler spacecraft. These five systems show transits from multiple exoplanet candidates. Should these objects prove to be planetary in nature, then these five systems open new opportunities for the field of exoplanets and provide new insights into the formation and dynamical evolution of planetary systems. We discuss the methods used to identify multiple transiting objects from the Kepler photometry as well as the false-positive rejection methods that have been applied to these data. One system shows transits from three distinct objects while the remaining four systems show transits from two objects. Three systems have planet candidates that are near mean motion commensurabilities-two near 2:1 and one just outside 5:2. We discuss the implications that multi-transiting systems have on the distribution of orbital inclinations in planetary systems, and hence their dynamical histories, as well as their likely masses and chemical compositions. A Monte Carlo study indicates that, with additional data, most of these systems should exhibit detectable transit timing variations (TTVs) due to gravitational interactions, though none are apparent in these data. We also discuss new challenges that arise in TTV analyses due to the presence of more than two planets in a system.Item Five-Year Wilkinson Microwave Anisotropy Probe Observations: Data Processing, Sky Maps, and Basic Results(2009-02) Hinshaw, G.; Weiland, J. L.; Hill, R. S.; Odegard, N.; Larson, D.; Bennett, C. L.; Dunkley, J.; Gold, B.; Greason, M. R.; Jarosik, N.; Komatsu, Eiichiro; Nolta, M. R.; Page, L.; Spergel, D. N.; Wollack, E.; Halpern, M.; Kogut, A.; Limon, M.; Meyer, S. S.; Tucker, G. S.; Wright, E. L.; Komatsu, EiichiroWe present new full-sky temperature and polarization maps in five frequency bands from 23 to 94 GHz, based on data from the first five years of the Wilkinson Microwave Anisotropy Probe (WMAP) sky survey. The new maps are consistent with previous maps and are more sensitive. The five-year maps incorporate several improvements in data processing made possible by the additional years of data and by a more complete analysis of the instrument calibration and in-flight beam response. We present several new tests for systematic errors in the polarization data and conclude that W-band polarization data is not yet suitable for cosmological studies, but we suggest directions for further study. We do find that Ka-band data is suitable for use; in conjunction with the additional years of data, the addition of Ka band to the previously used Q- and V-band channels significantly reduces the uncertainty in the optical depth parameter, tau. Further scientific results from the five-year data analysis are presented in six companion papers and are summarized in Section 7 of this paper. With the five-year WMAP data, we detect no convincing deviations from the minimal six-parameter Lambda CDM model: a flat universe dominated by a cosmological constant, with adiabatic and nearly scale-invariant Gaussian fluctuations. Using WMAP data combined with measurements of Type Ia supernovae and Baryon Acoustic Oscillations in the galaxy distribution, we find (68% CL uncertainties): Omega(b)h(2) = 0.02267(-0.00059)(+0.00058), Omega(c)h(2) = 0.1131 +/- 0.0034, Omega(Lambda) = 0.726 +/- 0.015, n(s) = 0.960 +/- 0.013, tau = 0.084 +/- 0.016, and Delta(2)(R) = (2.445 +/- 0.096) x 10(-9) at k = 0.002 Mpc(-1). From these we derive sigma(8) = 0.812 +/- 0.026, H(0) = 70.5 +/- 1.3 km s(-1) Mpc(-1), Omega(b) = 0.0456 +/- 0.0015, Omega(c) = 0.228 +/- 0.013, Omega(m)h(2) = 0.1358(-0.0036)(+0.0037), z(reion) = 10.9 +/- 1.4, and t(0) = 13.72 +/- 0.12 Gyr. The new limit on the tensor-to-scalar ratio is r < 0.22 (95% CL), while the evidence for a running spectral index is insignificant, dn(s)/d ln k = - 0.028 +/- 0.020 (68% CL). We obtain tight, simultaneous limits on the (constant) dark energy equation of state and the spatial curvature of the universe: - 0.14 < 1 + w < 0.12 (95% CL) and -0.0179 < Omega(k) < 0.0081 (95% CL). The number of relativistic degrees of freedom, expressed in units of the effective number of neutrino species, is found to be N(eff) = 4.4 +/- 1.5 (68% CL), consistent with the standard value of 3.04. Models with N(eff) = 0 are disfavored at >99.5% confidence. Finally, new limits on physically motivated primordial non-Gaussianity parameters are -9 < f(NL)(local) < 111 (95% CL) and -151 < f(NL)(equil) < 253 (95% CL) for the local and equilateral models, respectively.Item Inverting Color-Magnitude Diagrams To Access Precise Star Cluster Parameters: A New White Dwarf Age For The Hyades(2009-05) Degennaro, Steven; von Hippel, Ted; Jefferys, William H.; Stein, Nathan; van Dyk, David; Jeffery, Elizabeth; Degennaro, Steven; von Hippel, Ted; Jefferys, William H.; Stein, Nathan; Jeffery, ElizabethWe have extended our Bayesian modeling of stellar clusters-which uses main-sequence stellar evolution models, a mapping between initial masses and white dwarf (WD) masses, WD cooling models, and WD atmospheres-to include binary stars, field stars, and two additional main-sequence stellar evolution models. As a critical test of our Bayesian modeling technique, we apply it to Hyades UBV photometry, with membership priors based on proper motions and radial velocities, where available. Under the assumption of a particular set of WD cooling models and atmosphere models, we estimate the age of the Hyades based on cooling WDs to be 648 +/- 45 Myr, consistent with the best prior analysis of the cluster main-sequence turnoff (MSTO) age by Perryman et al. Since the faintest WDs have most likely evaporated from the Hyades, prior work provided only a lower limit to the cluster's WD age. Our result demonstrates the power of the bright WD technique for deriving ages and further demonstrates complete age consistency between WD cooling and MSTO ages for seven out of seven clusters analyzed to date, ranging from 150 Myr to 4 Gyr.Item Measurements Of The Rate Of Type Ia Supernovae At Redshift Less Than Or Similar To 0.3 From The Sloan Digital Sky Survey II Supernova Survey(2010-04) Dilday, Benjamin; Smith, Mathew; Bassett, Bruce; Becker, Andrew; Bender, Ralf; Castander, Francisco; Cinabro, David; Filippenko, Alexei V.; Frieman, Joshua A.; Galbany, Lluis; Garnavich, Peter M.; Goobar, Ariel; Hopp, Ulrich; Ihara, Yutaka; Jha, Saurabh W.; Kessler, Richard; Lampeitl, Hubert; Marriner, John; Miquel, Ramon; Molla, Mercedes; Nichol, Robert C.; Nordin, Jakob; Riess, Adam G.; Sako, Masao; Schneider, Donald P.; Sollerman, Jesper; Wheeler, J. Craig; Ostman, Linda; Bizyaev, Dmitry; Brewington, Howard; Malanushenko, Elena; Malanushenko, Viktor; Oravetz, Dan; Pan, Kaike; Simmons, Audrey; Snedden, Stephanie; Wheeler, J. CraigWe present ameasurement of the volumetric Type Ia supernova (SN Ia) rate based on data from the Sloan Digital Sky Survey II (SDSS-II) Supernova Survey. The adopted sample of supernovae (SNe) includes 516 SNe Ia at redshift z less than or similar to 0.3, of which 270(52%) are spectroscopically identified as SNe Ia. The remaining 246 SNe Ia were identified through their light curves; 113 of these objects have spectroscopic redshifts from spectra of their host galaxy, and 133 have photometric redshifts estimated from the SN light curves. Based on consideration of 87 spectroscopically confirmed non-Ia SNe discovered by the SDSS-II SN Survey, we estimate that 2.04+(1.61%)(-0.95) -0.95% of the photometric SNe Ia may be misidentified. The sample of SNe Ia used in this measurement represents an order of magnitude increase in the statistics for SN Ia rate measurements in the redshift range covered by the SDSS-II Supernova Survey. If we assume an SN Ia rate that is constant at low redshift (z < 0.15), then the SN observations can be used to infer a value of the SN rate of rV = (2.69(-0.30-0.01)(+ 0.34+ 0.21)) x 10(-5) SNe yr(-1) Mpc(-3) (H(0)/(70 km s(-1) Mpc(-1)))(3) at a mean redshift of similar to 0.12, based on 79 SNe Ia of which 72 are spectroscopically confirmed. However, the large sample of SNe Ia included in this study allows us to place constraints on the redshift dependence of the SN Ia rate based on the SDSS-II Supernova Survey data alone. Fitting a power-law model of the SN rate evolution, rV (z) = A(p) x((1 + z)/(1 + z(0)))(nu), over the redshift range 0.0 < z < 0.3 with z0 = 0.21, results in A(p) = (3.43+(+0.15)(-.015) SNe yr-1 Mpc-3 (H(0)/(70 km s(-1) Mpc(-1)))(3) and nu = 2.04(-0.89)(+0.89).Item Near-Infrared Line Identification In Type Ia Supernovae During The Transitional Phase(2014-09) Friesen, Brian; Baron, E.; Wisniewski, John P.; Parrent, Jerod T.; Thomas, R. C.; Miller, Timothy R.; Marion, G. H.; Marion, G. H.We present near-infrared synthetic spectra of a delayed-detonation hydrodynamical model and compare them to observed spectra of four normal Type Ia supernovae ranging from day +56.5 to day +85. This is the epoch during which supernovae are believed to be undergoing the transition from the photospheric phase, where spectra are characterized by line scattering above an optically thick photosphere, to the nebular phase, where spectra consist of optically thin emission from forbidden lines. We find that most spectral features in the near-infrared can be accounted for by permitted lines of Fe II and Co II. In addition, we find that [Ni II] fits the emission feature near 1.98 mu m, suggesting that a substantial mass of Ni-58 exists near the center of the ejecta in these objects, arising from nuclear burning at high density.Item Shear-Wave Splitting and Mantle Flow Beneath the Colorado Plateau and its Boundary with the Great Basin(2008-10) Wang, Xinling L.; Ni, James F.; Aster, Richard; Sandvol, Eric; Wilson, David; Sine, Christopher; Grand, Stephen P.; Baldridge, W. Scott; Wilson, David; Sine, Christopher; Grand, Stephen P.Shear-wave splitting measurements from SKS and SKKS phases show fast polarization azimuths that are subparallel to North American absolute plate motion within the central Rio Grande Rift (RGR) and Colorado Plateau (CP) through to the western rim of the CP, with anisotropy beneath the CP and central RGR showing a remarkably consistent pattern with a mean fast azimuth of 4 degrees +/- degrees 6 E of N. Approaching the rim from the southeast, fast anisotropic directions become north-northeast-south-southwest (NNE-SSW), rotate counter clockwise to north-south in the CP-GB transition, and then to NNW-SSE in the western Great Basin ( GB). This change is coincident with uppermost mantle S-wave velocity perturbations that vary from +4% beneath the western CP and the eastern edge of the Marysvale volcanic field to about -8% beneath the GB. Corresponding delay times average 1.5 sec beneath the central CP, decrease to approximately 0.8 sec near the CP-GB transition, and increase to about 1.2 sec beneath the GB. For the central CP, we suggest anisotropy predominantly controlled by North American plate motion above the asthenosphere. The observed pattern of westward-rotating anisotropy from the western CP through the CP-GB transition may be influenced to asthenospheric flow around a CP lithospheric keel and/or by vertical flow arising from edge-driven small-scale convection. The anisotropic transition from the CP to the GB thus marks a first-order change from absolute plate motion dominated lithosphere-asthenosphere shear to a new regime controlled by regional flow processes. The NNW-SSE anisotropic fast directions of split SKS waves in the eastern GB area are part of a broad circular pattern of seismic anisotropic fast direction in the central GB that has recently been hypothesized to be due to toroidal flow around the sinking Juan de Fuca-Gorda slab.Item The Sloan Digital Sky Survey-II Supernova Survey: Technical Summary(2008-01) Frieman, Joshua A.; Bassett, Bruce; Becker, Andrew; Choi, Changsu; Cinabro, David; DeJongh, Fritz; Depoy, Darren L.; Dilday, Ben; Doi, Mamoru; Garnavich, Peter M.; Hogan, Craig J.; Holtzman, Jon; Im, Myungshin; Jha, Saurabh; Kessler, Richard; Konishi, Kohki; Lampeitl, Hubert; Marriner, John; Marshall, Jennifer L.; McGinnis, David; Miknaitis, Gajus; Nichol, Robert C.; Prieto, Jose Luis; Riess, Adam G.; Richmond, Michael W.; Romani, Roger; Sako, Masao; Schneider, Donald P.; Smith, Mathew; Takanashi, Naohiro; Tokita, Kouichi; van der Heyden, Kurt; Yasuda, Naoki; Zheng, Chen; Adelman-McCarthy, Jennifer; Annis, James; Assef, Roberto J.; Barentine, John; Bender, Ralf; Blandford, Roger D.; Boroski, William N.; Bremer, Malcolm; Brewington, Howard; Collins, Chris A.; Crotts, Arlin; Dembicky, Jack; Eastman, Jason; Edge, Alastair; Edmondson, Edmond; Elson, Edward; Eyler, Michael E.; Filippenko, Alexei V.; Foley, Ryan J.; Frank, Stephan; Goobar, Ariel; Gueth, Tina; Gunn, James E.; Harvanek, Michael; Hopp, Ulrich; Ihara, Yutaka; Ivezić, Želko; Kahn, Steven; Kaplan, Jared; Kent, Stephen; Ketzeback, William; Kleinman, Scott J.; Kollatschny, Wolfram; Kron, Richard G; Krzesiński, Jurek; Lamenti, Dennis; Leloudas, Giorgos; Lin, Huan; Long, Daniel C.; Lucey, John; Lupton, Robert H.; Malanushenko, Elena; Malanushenko, Viktor; McMillan, Russet J.; Mendez, Javier; Morgan, Christopher W.; Morokuma, Tomoki; Nitta, Atsuko; Ostman, Linda; Pan, Kaike; Rockosi, Constance M.; Romer, A. Kathy; Ruiz-Lapuente, Pilar; Saurage, Gabrelle; Schlesinger, Katie; Snedden, Stephanie A.; Sollerman, Jesper; Stoughton, Chris; Stritzinger, Maximilian; SubbaRao, Mark; Tucker, Douglas; Vaisanen, Petri; Watson, Linda C.; Watters, Shannon; Wheeler, J. Craig; Yanny, Brian; York, Donald; Barentine, John; Wheeler, J. CraigThe Sloan Digital Sky Survey-II (SDSS-II) has embarked on a multi-year project to identify and measure light curves for intermediate-redshift (0.05 < z < 0.35) Type la supernovae (SNe Ia) using repeated five-band (ugriz) imaging over an area of 300 sq. deg. The survey region is a stripe 2.5 degrees wide centered on the celestial equator in the Southern Galactic Cap that has been imaged numerous times in earlier years, enabling construction of a deep reference image for the discovery of new objects. Supernova imaging observations are being acquired between September I and November 30 of 2005-7. During the first two seasons, each region was imaged on average every five nights. Spectroscopic follow-up observations to determine supernova type and redshift are carried out on a large number of telescopes. In its first two three-month seasons, the survey has discovered and measured light curves for 327 spectroscopically confirmed SNe Ia, 30 probable SNe Ia, 14 confirmed SNe Ib/c, 32 confirmed SNe 11, plus a large number of photometrically identified SNe la, 94 of which have host-galaxy spectra taken so far. This paper provides an overview of the project and briefly describes the observations completed during the first two seasons of operation.Item Taiwan’s Foreign Policy Transformation: Tsai Ing-wen and the New Southbound Policy(2023-05-04) Waltz, Cameron; Maclachlan, PatriciaThis thesis investigates the introduction of the New Southbound Policy and the evolution of Taiwan’s foreign policy more broadly. It asks why President Tsai Ing-wen introduced the New Southbound Policy, and how the NSP makes her foreign policy distinct from her predecessors. This thesis introduces an analytical framework for explaining how international forces, domestic forces, leadership, and constraints collectively shape Taiwan’s foreign policy. It then applies this framework to ROC Presidents Lee, Chen, Ma, and Tsai to explain their foreign policy choices. My argument is that Tsai Ing-wen introduced the New Southbound Policy as a response to both international and domestic concerns. The NSP was designed not only to further Tsai’s foreign policy interests by reducing economic dependence on China but also to serve her domestic agenda by delivering economic growth. At the same time, this thesis argues that the NSP was chosen over more aggressive options due to domestic political constraints and institutional constraints. The NSP sets Tsai’s foreign policy apart because it introduces new methods of economic and soft-power engagement that innovatively uses Taiwan’s limited set of foreign policy tools. Importantly, this thesis contributes to the existing literature by emphasizing the significant role that domestic politics and constraints play in motivating and shaping the foreign policy choices of Taiwan’s leaders.Item Tests Of The Radial Tremaine-Weinberg Method(2008-04) Meidt, S. E.; Rand, Richard J.; Merrifield, M. R.; Debattista, Victor P.; Shen, Juntai T.; Shen, Juntai T.At the intersection of galactic dynamics, evolution, and global structure, issues such as the relation between bars and spirals and the persistence of spiral patterns can be addressed through the characterization of the angular speeds of the patterns and their possible radial variation. The radial Tremaine-Weinberg (TWR) method, a generalized version of the Tremaine-Weinberg method for observationally determining a single, constant pattern speed, allows the pattern speed to vary arbitrarily with radius. Here we perform tests of the TWR method with regularization on several simulated galaxy data sets. The regularization is employed as a means of smoothing intrinsically noisy solutions, as well as for testing model solutions of different radial dependence (e. g., constant, linear, or quadratic). We test these facilities in studies of individual simulations and demonstrate successful measurement of both bar and spiral pattern speeds in a single disk, secondary bar pattern speeds, and spiral winding (in the first application of a TW calculation to a spiral simulation). We also explore the major sources of error in the calculation and find uncertainty in the major-axis position angle most dominant. In all cases, the method is able to extract pattern speed solutions where discernible patterns exist to within 20% of the known values, suggesting that the TWR method should be a valuable tool in the area of galactic dynamics. For utility, we also discuss the caveats in, and compile a prescription for, applications to real galaxies.Item The Very Young Type Ia Supernova 2012Cg: Discovery and Early-Time Follow-Up Observations(2012-09) Silverman, Jeffrey M.; Ganeshalingam, Mohan; Cenko, S. Bradley; Filippenko, Alexei V.; Li, Weidong; Barth, Aaron J.; Carson, Daniel J.; Childress, Michael; Clubb, Kelsey I.; Cucchiara, Antonino; Graham, Melissa L.; Marion, G. H.; Nguyen, My L.; Pei, Liuyi; Tucker, Brad E.; Vinko, Jozsef; Wheeler, J. Craig; Worseck, Gabor; Vinko, Jozsef; Wheeler, J. CraigOn 2012 May 17.2 UT, only 1.5 +/- 0.2 days after explosion, we discovered SN 2012cg, a Type Ia supernova (SN Ia) in NGC 4424 (d approximate to 15 Mpc). As a result of the newly modified strategy employed by the Lick Observatory Supernova Search, a sequence of filtered images was obtained starting 161 s after discovery. Utilizing recent models describing the interaction of supernova (SN) ejecta with a companion star, we rule out a similar to 1 M-circle dot companion for half of all viewing angles and a red-giant companion for nearly all orientations. SN 2012cg reached a B-band maximum of 12.09 +/- 0.02 mag on 2012 June 2.0 and took similar to 17.3 days from explosion to reach this, typical for SNe Ia. Our pre-maximum-brightness photometry shows a narrower-than-average B-band light curve for SN 2012cg, though slightly overluminous at maximum brightness and with normal color evolution (including some of the earliest SN Ia filtered photometry ever obtained). Spectral fits to SN 2012cg reveal ions typically found in SNe Ia at early times, with expansion velocities greater than or similar to 14,000 km s(-1) at 2.5 days past explosion. Absorption from C II is detected early, as well as high-velocity components of both Si II lambda 6355 and Ca II. Our last spectrum (13.5 days past explosion) resembles that of the somewhat peculiar SN Ia 1999aa. This suggests that SN 2012cg will have a slower-than-average declining light curve, which may be surprising given the faster-than-average rising light curve.Item Visitors from the Halo: 11 Gyr Old White Dwarfs in the Solar Neighborhood(2010-05) Kilic, Mukremin; Munn, Jeffrey A.; Williams, Kurtis A.; Kowalski, P. M.; von Hippel, Ted; Harris, Hugh C.; Jeffery, Elizabeth J.; DeGennaro, Steven; Brown, Warren R.; McLeod, B.; Williams, Kurtis A.We report the discovery of three nearby old halo white dwarf (WD) candidates in the Sloan Digital Sky Survey (SDSS), including two stars in a common proper motion binary system. These candidates are selected from our 2800 deg(2) proper motion survey on the Bok and U. S. Naval Observatory Flagstaff Station 1.3 m telescopes, and they display proper motions of 0.'' 4-0 ''.5 yr(-1). Follow-up MMT spectroscopy and near-infrared photometry demonstrate that all three objects are hydrogen-dominated atmosphere WDs with T(eff) approximate to 3700-4100 K. For average mass WDs, these temperature estimates correspond to cooling ages of 9-10 Gyr, distances of 70-80 pc, and tangential velocities of 140-200 km s(-1). Based on the UVW space velocities, we conclude that they most likely belong to the halo. Furthermore, the combined main-sequence and WD cooling ages are 10-11 Gyr. Along with SDSS J1102+4113, they are the oldest field WDs currently known. These three stars represent only a small fraction of the halo WD candidates in our proper motion survey, and they demonstrate that deep imaging surveys like the Pan-STARRS and Large Synoptic Survey Telescope should find many old thick disk and halo WDs that can be used to constrain the age of the Galactic thick disk and halo.Item White Dwarf Luminosity And Mass Functions From Sloan Digital Sky Survey Spectra(2008-01) DeGennaro, Steven; von Hippel, Ted; Winget, D. E.; Kepler, S. O.; Nitta, Atsuko; Koester, Detlev; Althaus, Leandro; DeGennaro, Steven; von Hippel, Ted; Winget, D. E.We present the first phase in our ongoing work to use Sloan Digital Sky Survey (SDSS) data to create separate white dwarf (WD) luminosity functions (LFs) for two or more different mass ranges. In this paper, we determine the completeness of the SDSS spectroscopic WD sample by comparing a proper-motion selected sample of WDs from SDSS imaging data with a large catalog of spectroscopically determined WDs. We derive a selection probability as a function of a single color (g - i) and apparent magnitude (g) that covers the range - 1.0 < g - i < 0.2 and 15 < g < 19.5. We address the observed upturn in log g for WDs with T-eff less than or similar to 12,000 K and offer arguments that the problem is limited to the line profiles and is not present in the continuum. We offer an empirical method of removing the upturn, recovering a reasonable mass function for WDs with T-eff < 12,000 K. Finally, we present a WD LF with nearly an order of magnitude (3358) more spectroscopically confirmed WDs than any previous work.Item White Dwarf Luminosity And Mass Functions From Sloan Digital Sky Survey Spectra(2008-01) DeGennaro, Steven; von Hippel, Ted; Winget, D. E.; Kepler, S. O.; Nitta, Atsuko; Koester, Detlev; Althaus, Leandro; DeGennaro, Steven; von Hippel, Ted; Winget, D. E.We present the first phase in our ongoing work to use Sloan Digital Sky Survey (SDSS) data to create separate white dwarf (WD) luminosity functions (LFs) for two or more different mass ranges. In this paper, we determine the completeness of the SDSS spectroscopic WD sample by comparing a proper-motion selected sample of WDs from SDSS imaging data with a large catalog of spectroscopically determined WDs. We derive a selection probability as a function of a single color (g - i) and apparent magnitude (g) that covers the range - 1.0 < g - i < 0.2 and 15 < g < 19.5. We address the observed upturn in log g for WDs with T-eff less than or similar to 12,000 K and offer arguments that the problem is limited to the line profiles and is not present in the continuum. We offer an empirical method of removing the upturn, recovering a reasonable mass function for WDs with T-eff < 12,000 K. Finally, we present a WD LF with nearly an order of magnitude (3358) more spectroscopically confirmed WDs than any previous work.Item The White Dwarf Population In NGC 1039 (M34) And The White Dwarf Initial-Final Mass Relation(2008-06) Rubin, Kate H. R.; Williams, Kurtis A.; Bolte, M.; Koester, Detlev; Williams, Kurtis A.We present the first detailed photometric and spectroscopic study of the white dwarfs (WDs) in the field of the similar to 225 Myr old (log tau(cl) = 8.35) open cluster NGC 1039 (M34) as part of the ongoing Lick-Arizona White Dwarf Survey. Using wide-field UBV imaging, we photometrically select 44 WD candidates in this field. We spectroscopically identify 19 of these objects as WDs; 17 are hydrogen-atmosphere DA WDs, one is a helium-atmosphere DB WD, and one is a cool DC WD that exhibits no detectable absorption lines. We find an effective temperature (T(eff)) and surface gravity (log g) for each DA WD by fitting Balmer-line profiles from model atmospheres to the observed spectra. WD evolutionary models are then invoked to derive masses and cooling times for each DA WD. Of the 17 DAs, five are at the approximate distance modulus of the cluster. Another WD with a distance modulus 0.45 mag brighter than that of the cluster could be a double-degenerate binary cluster member, but is more likely to be a field WD. We place the five single cluster member WDs in the empirical initial-final mass relation and find that three of them lie very close to the previously derived linear relation; two have WD masses significantly below the relation. These outliers may have experienced some sort of enhanced mass loss or binary evolution; however, it is quite possible that these WDs are simply interlopers from the field WD population. Eight of the 17 DA WDs show significant Ca II K absorption; comparison of the absorption strength with the WD distances suggests that the absorption is interstellar, though this cannot be confirmed with the current data.